Cpp program to search an element in an array using binary search

Write a program to search an element in a sorted array

Solution

#include<iostream>
using namespace std;
int main(){
    int arr[50],size,i,item,upper,lower=0,mid,flag=0;
    cout<<"Enter the desired array size "<<endl;
    cin>>size;
    cout<<"Enter the elements(Sorted in ascending order) "<<endl;
    for(i=0;i<size;i++)
    {
        cin>>arr[i];
    }
    cout<<"Enter the element to be searched for :";
    cin>>item;
    upper=size-1;
    while(lower<=upper)
    {
        mid=(upper+lower)/2;
        if(item==arr[mid])
        {
            flag=1;
            break;
        }
        else if(item<arr[mid])
        {
            upper=mid-1;
        }
        else
        {
            lower=mid+1;
        }
    }
    if(flag==1)
    {
        cout<<"Element found at index "<<mid<<" position "<<mid+1;
    }
    else
    {
        cout<<"Element not found"<<endl;
    }
    return 0;
}

Output

Enter the desired array size

10

Enter the elements(Sorted in ascending order)

2

3

5

9

12

15

20

23

25

30

Enter the element to be searched for :20

Element found at index 6 position 7

Programming Examples

Cpp program to search an element in an array using binary search